307 research outputs found

    Higher media multi-tasking activity is associated with smaller gray-matter density in the anterior cingulate cortex

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    Media multitasking, or the concurrent consumption of multiple media forms, is increasingly prevalent in today’s society and has been associated with negative psychosocial and cognitive impacts. Individuals who engage in heavier media-multitasking are found to perform worse on cognitive control tasks and exhibit more socio-emotional difficulties. However, the neural processes associated with media multi-tasking remain unexplored. The present study investigated relationships between media multitasking activity and brain structure. Research has demonstrated that brain structure can be altered upon prolonged exposure to novel environments and experience. Thus, we expected differential engagements in media multitasking to correlate with brain structure variability. This was confirmed via Voxel-Based Morphometry (VBM) analyses: Individuals with higher Media Multitasking Index (MMI) scores had smaller gray matter density in the anterior cingulate cortex (ACC). Functional connectivity between this ACC region and the precuneus was negatively associated with MMI. Our findings suggest a possible structural correlate for the observed decreased cognitive control performance and socio-emotional regulation in heavy media-multitaskers. While the cross-sectional nature of our study does not allow us to specify the direction of causality, our results brought to light novel associations between individual media multitasking behaviors and ACC structure differences

    A self-organized model for cell-differentiation based on variations of molecular decay rates

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    Systemic properties of living cells are the result of molecular dynamics governed by so-called genetic regulatory networks (GRN). These networks capture all possible features of cells and are responsible for the immense levels of adaptation characteristic to living systems. At any point in time only small subsets of these networks are active. Any active subset of the GRN leads to the expression of particular sets of molecules (expression modes). The subsets of active networks change over time, leading to the observed complex dynamics of expression patterns. Understanding of this dynamics becomes increasingly important in systems biology and medicine. While the importance of transcription rates and catalytic interactions has been widely recognized in modeling genetic regulatory systems, the understanding of the role of degradation of biochemical agents (mRNA, protein) in regulatory dynamics remains limited. Recent experimental data suggests that there exists a functional relation between mRNA and protein decay rates and expression modes. In this paper we propose a model for the dynamics of successions of sequences of active subnetworks of the GRN. The model is able to reproduce key characteristics of molecular dynamics, including homeostasis, multi-stability, periodic dynamics, alternating activity, differentiability, and self-organized critical dynamics. Moreover the model allows to naturally understand the mechanism behind the relation between decay rates and expression modes. The model explains recent experimental observations that decay-rates (or turnovers) vary between differentiated tissue-classes at a general systemic level and highlights the role of intracellular decay rate control mechanisms in cell differentiation.Comment: 16 pages, 5 figure

    Using honey to heal diabetic foot ulcers

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    Diabetic ulcers seem to be arrested in the inflammatory/proliferative stage of the healing process, allowing infection and inflammation to preclude healing. Antibiotic-resistant bacteria have become a major cause of infections, including diabetic foot infections. It is proposed here that the modern developments of an ancient and traditional treatment for wounds, dressing them with honey, provide the solution to the problem of getting diabetic ulcers to move on from the arrested state of healing. Honeys selected to have a high level of antibacterial activity have been shown to be very effective against antibiotic-resistant strains of bacteria in laboratory and clinical studies. The potent anti-inflammatory action of honey is also likely to play an important part in overcoming the impediment to healing that inflammation causes in diabetic ulcers, as is the antioxidant activity of honey. The action of honey in promotion of tissue regeneration through stimulation of angiogenesis and the growth of fibroblasts and epithelial cells, and its insulin-mimetic effect, would also be of benefit in stimulating the healing of diabetic ulcers. The availability of honey-impregnated dressings which conveniently hold honey in place on ulcers has provided a means of rapidly debriding ulcers and removing the bacterial burden so that good healing rates can be achieved with neuropathic ulcers. With ischemic ulcers, where healing cannot occur because of lack of tissue viability, these honey dressings keep the ulcers clean and prevent infection occurring

    Neurologic adverse events associated with smallpox vaccination in the United States – response and comment on reporting of headaches as adverse events after smallpox vaccination among military and civilian personnel

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    BACKGROUND: Accurate reporting of adverse events occurring after vaccination is an important component of determining risk-benefit ratios for vaccinations. Controversy has developed over alleged underreporting of adverse events within U.S. military samples. This report examines the accuracy of adverse event rates recently published for headaches, and examines the issue of underreporting of headaches as a function of civilian or military sources and as a function of passive versus active surveillance. METHODS: A report by Sejvar et al was examined closely for accuracy with respect to the reporting of neurologic adverse events associated with smallpox vaccination in the United States. Rates for headaches were reported by several scholarly sources, in addition to Sejvar et al, permitting a comparison of reporting rates as a function of source and type of surveillance. RESULTS: Several major errors or omissions were identified in Sejvar et al. The count of civilian subjects vaccinated and the totals of both civilians and military personnel vaccinated were reported incorrectly by Sejvar et al. Counts of headaches reported in VAERS were lower (n = 95) for Sejvar et al than for Casey et al (n = 111) even though the former allegedly used 665,000 subjects while the latter used fewer than 40,000 subjects, with both using approximately the same civilian sources. Consequently, rates of nearly 20 neurologic adverse events reported by Sejvar et al were also incorrectly calculated. Underreporting of headaches after smallpox vaccination appears to increase for military samples and for passive adverse event reporting systems. CONCLUSION: Until revised or corrected, the rates of neurologic adverse events after smallpox vaccinated reported by Sejvar et al must be deemed invalid. The concept of determining overall rates of adverse events by combining small civilian samples with large military samples appears to be invalid. Reports of headaches as adverse events after smallpox vaccination appear to be have occurred much less frequently using passive surveillance systems and by members of the U.S. military compared to civilians, especially those employed in healthcare occupations. Such concerns impact risk-benefit ratios associated with vaccines and weigh against making vaccinations mandatory, without informed consent, even among military members. Because of the issues raised here, adverse event rates derived solely or primarily from U.S. Department of Defense reporting systems, especially passive surveillance systems, should not be used, given better alternatives, for making public health policy decisions

    Demographic and Clinical Factors Associated with Response to Smallpox Vaccine in Preimmunized Volunteers

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    CONTEXT: In March 2003, the French Ministry of Health implemented a program on preparedness and response to a biological attack using smallpox as weapon. This program included the establishment of a preoutbreak national team that could be revaccinated against smallpox. OBJECTIVE: To identify demographic and clinical factors associated with vaccination success defined as the presence of a pustule at the inoculation site at day 8 (days 7-9), with an undiluted vaccinia virus derived from a Lister strain among preimmunized volunteers. VOLUNTEERS AND METHODS: From March 2003 to November 2006, we have studied prospectively 226 eligible volunteers. Demographic data were recorded for each volunteer (age, sex, number of previously smallpox vaccinations and date of the last vaccination). Smallpox vaccine adverse reactions were diagnosed on the basis of clinical examination performed at days 0, 7, 14, 21 and 28 after revaccination. RESULTS: A total of 226 volunteers (sex ratio H/F = 2.7) were revaccinated. Median age was 45 years (range: 27-63 yrs). All volunteers completed follow-up. Median number of vaccinations before revaccination was 2 (range: 1-8). The median delay between time of the study and the last vaccination was 29 years (range; 18-60 yrs). Sixty-one volunteers (27%) experienced one (n = 40) or more (n = 21) minor side effects during the 2-14 days after revaccination. Successful vaccination was noted in 216/226 volunteers (95.6%) at day 8 and the median of the pustule diameter was 5 mm (range: 1-20 mm). Size of the pustule at day 8 was correlated with age (p = 0.03) and with the presence of axillary adenopathy after revaccination (p = 0.007). Sex, number of prior vaccinations, delay between the last vaccination and revaccination, and local or systemic side effects with the exception of axillary adenopathy, were not correlated with the size of the pustule at day 8. CONCLUSIONS: Previously vaccinated volunteers can be successfully revaccinated with the Lister strain

    The CHIP-Family study to improve the psychosocial wellbeing of young children with congenital heart disease and their families: design of a randomized controlled trial

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    Background: Children with congenital heart disease (CHD) are at increased risk for behavioral, emotional, and cognitive problems. They often have reduced exercise capacity and participate less in sports, which is associated with a lower quality of life. Starting school may present more challenges for children with CHD and their families than for families with healthy children. Moreover, parents of children with CHD are at risk for psychosocial problems. Therefore, a family-centered psychosocial intervention for children with CHD when starting school is needed. Until now, the 'Congenital Heart Disease Intervention Program (CHIP) - School' is the only evidence-based intervention in this field. However, CHIP-School targeted parents only and resulted in non-significant, though positive, effects as to child psychosocial wellbeing. Hence, we expanded CHIP by adding a specific child module and including siblings, creating the CHIP-Family intervention. The CHIP-Family study aims to (1) test the effects of CHIP-Family on parental mental health and psychosocial wellbeing of CHD-children and to (2) identify baseline psychosocial and medical predictors for the e

    The Gaia-ESO survey: Matching chemodynamical simulations to observations of the Milky Way

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    The typical methodology for comparing simulated galaxies with observational surveys is usually to apply a spatial selection to the simulation to mimic the region of interest covered by a comparable observational survey sample. In this work we compare this approach with a more sophisticated post-processing in which the observational uncertainties and selection effects (photometric, surface gravity and effective temperature) are taken into account. We compare a `solar neighbourhood analogue' region in a model Milky Way-like galaxy simulated with RAMSES-CH with fourth release Gaia-ESO survey data. We find that a simple spatial cut alone is insufficient and that observational uncertainties must be accounted for in the comparison. This is particularly true when the scale of uncertainty is large compared to the dynamic range of the data, e.g. in our comparison, the [Mg/Fe] distribution is affected much more than the more accurately determined [Fe/H] distribution. Despite clear differences in the underlying distributions of elemental abundances between simulation and observation, incorporating scatter to our simulation results to mimic observational uncertainty produces reasonable agreement. The quite complete nature of the Gaia-ESO survey means that the selection function has minimal impact on the distribution of observed age and metal abundances but this would become increasingly more important for surveys with narrower selection functions

    Comprehensive analysis of blood cells and plasma identifies tissue-specific miRNAs as potential novel circulating biomarkers in cattle

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    Abstract Background The potential of circulating miRNAs as biomarkers of tissue function, both in health and disease, has been extensively demonstrated in humans. In addition, circulating miRNA biomarkers offer significant potential towards improving the productivity of livestock species, however, such potential has been hampered by the absence of information on the nature and source of circulating miRNA populations in these species. In addition, many miRNAs originally proposed as robust biomarkers of a particular tissue or disease in humans have been later shown not to be tissue specific and thus to actually have limited biomarker utility. In this study, we comprehensively analysed miRNA profiles in plasma and cell fractions of blood from cattle with the aim to identify tissue-derived miRNAs which may be useful as biomarkers of tissue function in this important food animal species. Results Using small RNA sequencing, we identified 92 miRNAs with significantly higher expression in plasma compared to paired blood cell samples (n = 4 cows). Differences in miRNA levels between plasma and cell fractions were validated for eight out of 10 miRNAs using RT-qPCR (n = 10 cows). Among miRNAs found to be enriched in plasma, we confirmed miR-122 (liver), miR-133a (muscle) and miR-215 (intestine) to be tissue-enriched, as reported for other species. Profiling of additional miRNAs across different tissues identified the human homologue, miR-802, as highly enriched specifically in liver. Conclusions These results provide novel information on the source of bovine circulating miRNAs and could significantly facilitate the identification of production-relevant tissue biomarkers in livestock. In particular, miR-802, a circulating miRNA not previously identified in cattle, can reportedly regulate insulin sensitivity and lipid metabolism, and thus could potentially provide a specific biomarker of liver function, a key parameter in the context of post-partum negative energy balance in dairy cows

    Non-capsulated and capsulated Haemophilus influenzae in children with acute otitis media in Venezuela: a prospective epidemiological study

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    <p>Abstract</p> <p>Background</p> <p>Non-typeable <it>Haemophilus influenzae </it>(NTHi) and <it>Streptococcus pneumoniae </it>are major causes of bacterial acute otitis media (AOM). Data regarding AOM are limited in Latin America. This is the first active surveillance in a private setting in Venezuela to characterize the bacterial etiology of AOM in children < 5 years of age.</p> <p>Methods</p> <p>Between December 2008 and December 2009, 91 AOM episodes (including sporadic, recurrent and treatment failures) were studied in 87 children enrolled into a medical center in Caracas, Venezuela. Middle ear fluid samples were collected either by tympanocentesis or spontaneous otorrhea swab sampling method. Standard laboratory and microbiological techniques were used to identify bacteria and test for antimicrobial resistance. The results were interpreted according to Clinical Laboratory Standards Institute (CLSI) 2009 for non-meningitis isolates. All statistical analyses were performed using SAS 9.1 and Microsoft Excel (for graphical purposes).</p> <p>Results</p> <p>Overall, bacteria were cultured from 69.2% (63 of the 91 episodes); at least one pathogen (<it>S. pneumoniae, H. influenzae, S. pyogenes </it>or <it>M. catarrhalis</it>) was cultured from 65.9% (60/91) of episodes. <it>H. influenzae </it>(55.5%; 35/63 episodes) and <it>S. pneumoniae </it>(34.9%; 22/63 episodes) were the most frequently reported bacteria. Among <it>H. influenzae </it>isolates, 62.9% (22/35 episodes) were non-capsulated (NTHi) and 31.4% (11/35 episodes) were capsulated including types d, a, c and f, across all age groups. Low antibiotic resistance for <it>H. influenzae </it>was observed to amoxicillin/ampicillin (5.7%; 2/35 samples). NTHi was isolated in four of the six <it>H. influenzae </it>positive samples (66.7%) from recurrent episodes.</p> <p>Conclusions</p> <p>We found <it>H. influenzae </it>and <it>S. pneumoniae </it>to be the main pathogens causing AOM in Venezuela. Pneumococcal conjugate vaccines with efficacy against these bacterial pathogens may have the potential to maximize protection against AOM.</p

    Psychiatric Context of Acute/Early HIV Infection. The NIMH Multisite Acute HIV Infection Study: IV

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    Acute/early HIV infection is a period of high risk for HIV transmission. Better understanding of behavioral aspects during this period could improve interventions to limit further transmission. Thirty-four participants with acute/early HIV infection from six US cities were assessed with the Mini International Diagnostic Interview, Beck Depression Inventory II, State-Trait Anxiety Inventory, Brief COPE, and an in-depth interview. Most had a pre-HIV history of alcohol or substance use disorder (85%); a majority (53%) had a history of major depressive or bipolar disorder. However, post-diagnosis coping was predominantly adaptive, with only mild to moderate elevations of anxious or depressive mood. Respondents described challenges managing HIV in tandem with pre-existing substance abuse problems, depression, and anxiety. Integration into medical and community services was associated with adaptive coping. The psychiatric context of acute/early HIV infection may be a precursor to infection, but not necessarily a barrier to intervention to reduce forward transmission of HIV among persons newly infected
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